Roberto, its a kit with different mouth pieces for the Suzuki Melodeons. I purchased one several years ago when they first came our. if you like the selection of mouth pieces then its fine if you only use one type its not worth the cost if you do not use the different mouth pieces.
Almost all of those mouthpieces can be found now at reasonable individual prices on eBay. As the incurable minimalist, I’m partial to the little one that looks like a chess pawn, the MP-142. There’s a trombone model the MP-191, two trumpets the MP-131 and 132; the one with the gold colored tip is the MP-141, which comes with the ProV37 and Hammond 44; the standard Suzuki mouthpiece is also in the kit, the MP-121. I don’t know the one in the middle. If you don’t see the one you want on eBay, check back, as they come and go.